Beat deafness: développement d'un outil de dépistage et nouveaux cas.

Le terme beat deafness désigne une forme d’amusie congénitale spécifique à l’aspect temporel en musique qui a été découverte récemment par l’étude d’un cas unique (Phillips-Silver et al., 2011). L’objectif principal de ce mémoire était d’identifier de nouveaux cas. Nous avons évalué, chez 100 étudiants universitaires, les capacités à percevoir le beat à se synchroniser sur celui-ci. Les capacités de perception ont été évaluées au moyen de deux tests: un test de détection de perturbations rythmiques et un test de classification de courts extraits musicaux en marches et valses. Les capacités de synchronisation ont été évaluées au moyen d’une tâche consistant à taper du doigt sur les temps forts des mêmes marches et valses. Quatre personnes se sont démarquées du groupe par des difficultés de perception et de synchronisation, et sont dès lors considérées comme des nouveaux cas de beat deafness.

The prevalence of congenital amusia

L’amusie congénitale est un trouble neurogénétique qui se caractérise par une inhabileté à acquérir des habiletés musicales de base, telles que la perception musicale et la reconnaissance musicale normales, malgré une audition, un développement du langage et une intelligence normaux (Ayotte, Peretz & Hyde, 2002). Récemment, une éude d’aggrégation familiale a démontré que 39% des membres de familles d’individus amusiques démontrent le trouble, comparativement à 3% des membres de familles d’individus normaux (Peretz et al., 2007). Cette conclusion est intéressante puisqu’elle démontre une prévalence de l’amusie congénitale dans la population normale. Kalmus et Fry (1980) ont évalué cette prévalence à 4%, en utilisant le Distorted Tunes Test (DTT). Par contre, ce test présente certaines lacunes méthodologiques et statistiques, telles un effet plafond important, ainsi que l’usage de mélodies folkloriques, désavantageant les amusiques puisque ceux-ci ne peuvent pas assimiler ces mélodies correctement. L’étude présente visait à réévaluer la prévalence de l’amusie congénitale en utilisant un test en ligne récemment validé par Peretz et ses collègues (2008). Mille cent participants, d’un échantillon homogène, ont complété le test en ligne. Les résultats démontrent une prévalence globale de 11.6%, ainsi que quatre profiles de performance distincts: pitch deafness (1.5%), pitch memory amusia (3.2%), pitch perception amusia (3.3%), et beat deafness (3.3%). La variabilité des résultats obtenus avec le test en ligne démontre l’existence de quatre types d’amusies avec chacune une prévalence individuelle, indiquant une hétérogénéité dans l’expression de l’amusie congénitale qui devra être explorée ultérieurement.

A novel missense mutation p.L76P in the GJB2 gene causing nonsyndromic recessive deafness in a Brazilian family

Mutations in the GJB2 gene, encoding connexin 26 (Cx26), are a major cause of nonsyndromic recessive hearing loss in many countries. We report here on a novel point mutation in GJB2, p.L76P (c.227C>T), in compound heterozygosity with a c.35delG mutation, in two Brazilian sibs, one presenting mild and the other profound nonsyndromic neurosensorial hearing impairment. Their father, who carried a wild-type allele and a p.L76P mutation, had normal hearing. The mutation leads to the substitution of leucine (L) by proline (P) at residue 76, an evolutionarily conserved position in Cx26 as well as in other connexins. This mutation is predicted to affect the first extracellular domain (EC1) or the second transmembrane domain (TM2). EC1 is important for connexon-connexon interaction and for the control of channel voltage gating. The segregation of the c.227C>T (p.L76P) mutation together with c.35delG in this family indicates a recessive mode of inheritance. The association between the p.L76P mutation and hearing impairment is further supported by its absence in a normal hearing control group of 100 individuals, 50 European-Brazilians and 50 African-Brazilians.

A method to lower the detection limit for optical beat signals from a frequency-dithered stabilized laser

A narrow absorption feature in an atomic or molecular gas (such as iodine or methane) is used as the frequency reference in many stabilized lasers. As part of the stabilization scheme an optical frequency dither is applied to the laser. In optical heterodyne experiments, this dither is transferred to the RF beat signal, reducing the spectral power density and hence the signal to noise ratio over that in the absence of dither. We removed the dither by mixing the raw beat signal with a dithered local oscillator signal. When the dither waveform is matched to that of the reference laser the output signal from the mixer is rendered dither free. Application of this method to a Winters iodine-stabilized helium-neon laser reduced the bandwidth of the beat signal from 6 MHz to 390 kHz, thereby lowering the detection threshold from 5 pW of laser power to 3 pW. In addition, a simple signal detection model is developed which predicts similar threshold reductions.

Male Teachers in Feminised Teaching Areas: marching to the beat of the men's movement drums?

Calls for more male teachers are prevalent in current gender debates in education. A dominant argument in this debate is that boys are often alienated from school because of a lack of male role models in feminised areas of the school curriculum and in primary schools. Little research has investigated male teachers' accounts of their work within feminised environments. Drawing on data collected in two research studies in music education, this paper focuses on accounts given by male teachers about (a) practices adopted specifically to work with boys and (b) the role of the male music teacher. Analysis of these data suggests that some male teachers working in feminised areas of the school curriculum adopt practices which, rather than challenging dominant constructions of masculinity, sometimes reinforce gender stereotypical behaviours in boys. We argue that calls for increasing the number of male teachers in feminised areas of schooling need also to be informed by open discussion of the underlying assumptions about masculinity which teachers themselves bring to their work.

Microangiopathy of the inner ear, deafness, and cochlear implantation in a patient with Susac syndrome

Conclusion: The cochlear implant was beneficial as an attempt to restore hearing and improve communication abilities in this patient with profound sensorineural hearing loss secondary to Susac syndrome. Objective: To report the audiological outcomes of cochlear implantation (CI) in a young woman with Susac syndrome after a 6-month follow-up period. Susac syndrome is a rare disorder. It is clinically characterized by a typical triad of sensorineural deafness, encephalopathy, and visual defect, due to microangiopathy involving the brain, inner ear, and retina. Methods: This was a retrospective review of a case at a tertiary referral center. After diagnosis, the patient was evaluated by a multidisciplinary team and received a cochlear implant in her right ear. Results: The patient achieved 100% open-set sentence recognition in noise conditions and 92% monosyllable and 68% medial consonant recognition in quiet conditions after 6 months of implant use. She reported the use of the telephone 3 months after activation.

Primary ciliary dyskinesia: evaluation using cilia beat frequency assessment via spectral analysis of digital microscopy images

Olm MA, Kogler JE Jr, Macchione M, Shoemark A, Saldiva PH, Rodrigues JC. Primary ciliary dyskinesia: evaluation using cilia beat frequency assessment via spectral analysis of digital microscopy images. J Appl Physiol 111: 295-302, 2011. First published May 5, 2011; doi:10.1152/japplphysiol.00629.2010.-Ciliary beat frequency (CBF) measurements provide valuable information for diagnosing of primary ciliary dyskinesia (PCD). We developed a system for measuring CBF, used it in association with electron microscopy to diagnose PCD, and then analyzed characteristics of PCD patients. 1 The CBF measurement system was based on power spectra measured through digital imaging. Twenty-four patients suspected of having PCD (age 1-19 yr) were selected from a group of 75 children and adolescents with pneumopathies of unknown causes. Ten healthy, nonsmoking volunteers (age >= 17 yr) served as a control group. Nasal brush samples were collected, and CBF and electron microscopy were performed. PCD was diagnosed in 12 patients: 5 had radial spoke defects, 3 showed absent central microtubule pairs with transposition, 2 had outer dynein arm defects, 1 had a shortened outer dynein arm, and 1 had a normal ultrastructure. Previous studies have reported that the most common cilia defects are in the dynein arm. As expected, the mean CBF was higher in the control group (P < 0.001) and patients with normal ultrastructure (P < 0.002), than in those diagnosed with cilia ultrastructural defects (i.e., PCD patients). An obstructive ventilatory pattern was observed in 70% of the PCD patients who underwent pulmonary function tests. All PCD patients presented bronchial wall thickening on chest computed tomography scans. The protocol and diagnostic techniques employed allowed us to diagnose PCD in 16% of patients in this study.

Relational learning in children with deafness and cochlear implants

This four-experiment series sought to evaluate the potential of children with neurosensory deafness and cochlear implants to exhibit auditory-visual and visual-visual stimulus equivalence relations within a matching-to-sample format. Twelve children who became deaf prior to acquiring language (prelingual) and four who became deaf afterwards (postlingual) were studied. All children learned auditory-visual conditional discriminations and nearly all showed emergent equivalence relations. Naming tests, conducted with a subset of the: children, showed no consistent relationship to the equivalence-test outcomes.. This study makes several contributions: to the literature on stimulus equivalence. First; it demonstrates that both pre- and postlingually deaf children-can: acquire auditory-visual equivalence-relations after cochlear implantation, thus demonstrating symbolic functioning. Second, it directs attention to a population that may be especially interesting for researchers seeking to analyze the relationship. between speaker and listener repertoires. Third, it demonstrates the feasibility of conducting experimental studies of stimulus control processes within the limitations of a hospital, which these children must visit routinely for the maintenance of their cochlear implants.

Drawing insight from pictures: The development of concepts of false drawing and false belief in children with deafness, normal hearing, and autism

Theory-of-mind concepts in children with deafness, autism, and normal development (N = 154) were examined in three experiments using a set of standard inferential false-belief tasks and matched sets of tasks involving false drawings. Results of all three experiments replicated previously published findings by showing that primary school children with deafness or autism, aged 6 to 13 years, scored significantly lower than normal-developing 4-year-old preschoolers on standard misleading-container and unseen-change tests of false-belief understanding. Furthermore, deaf and autistic children generally scored higher on drawing-based tests than on corresponding standard tests and, on the most challenging of the false-drawing tests in Experiment 2, they significantly outperformed the normal-developing preschoolers by clearly understanding their own false intentions and another person's false beliefs about an actively misleading drawing. In Experiment 3, preschoolers; outperformed older deaf and autistic children on standard tasks, but did less well on a task that required the drawing of a false belief. Methodological factors could not fully explain the findings, but early social and conversational experiences in the family were deemed likely contributors.

Time-frequency and time-scale characterisation of the beat-by-beat high-resolution electrocardiogram

Proceedings of the Sixth Portuguese Conference on Bioemedical Engineering faro, Portugal

Association of mutations in the NALP3/CIAS1/PYPAF1 gene with a broad phenotype including recurrent fever, cold sensitivity, sensorineural deafness, and AA amyloidosis.

OBJECTIVE: Familial cold urticaria (FCU) and Muckle-Wells syndrome (MWS) are dominantly inherited autoinflammatory disorders that cause rashes, fever, arthralgia, and in some subjects, AA amyloidosis, and have been mapped to chromosome 1q44. Sensorineural deafness in MWS, and provocation of symptoms by cold in FCU, are distinctive features. This study was undertaken to characterize the genetic basis of FCU, MWS, and an overlapping disorder in French Canadian, British, and Indian families, respectively. METHODS: Mutations in the candidate gene NALP3, which has also been named CIAS1 and PYPAF1, were sought in the study families, in a British/Spanish patient with apparent sporadic MWS, and in matched population controls. Identified variants were sought in 50 European subjects with uncharacterized, apparently sporadic periodic fever syndromes, 48 subjects with rheumatoid arthritis (RA), and 19 subjects with juvenile idiopathic arthritis (JIA). RESULTS: Point mutations, encoding putative protein variants R262W and L307P, were present in all affected members of the Indian and French Canadian families, respectively, but not in controls. The R262W variant was also present in the subject with sporadic MWS. The V200M variant was present in all affected members of the British family with MWS, in 2 of the 50 subjects with uncharacterized periodic fevers, and in 1 of 130 Caucasian and 2 of 48 Indian healthy controls. No mutations were identified among the subjects with RA or JIA. CONCLUSION: These findings confirm that mutations in the NALP3/CIAS1/PYPAF1 gene are associated with FCU and MWS, and that disease severity and clinical features may differ substantially within and between families. Analysis of this gene will improve classification of patients with inherited or apparently sporadic periodic fever syndromes.

Intel·ligència artificial aplicada a un joc beat'em up en 2D

Creació d'un joc del tipus Arcade beat'em up en 2D utilitzant escenaris amb una certa profunditat de moviment i dotant als personatges no jugadors i altres objectes d'Intel·ligència Artificial de manera que el seu comportament no sigui sempre lineal i aprofitant-ho per afegir nivells de dificultat.

Assessment of left coronary artery beat-to-beat repositioning in order to propose an optimal acquisition window for coronary MRA

Introduction: Coronary magnetic resonance angiography (MRA) is a medical imaging technique that involves collecting data from consecutive heartbeats, always at the same time in the cardiac cycle, in order to minimize heart motion artifacts. This technique relies on the assumption that coronary arteries always follow the same trajectory from heartbeat to heartbeat. Until now, choosing the acquisition window in the cardiac cycle was based exclusively on the position of minimal coronary motion. The goal of this study was to test the hypothesis that there are time intervals during the cardiac cycle when coronary beat-to-beat repositioning is optimal. The repositioning uncertainty values in these time intervals were then compared with the intervals of low coronary motion in order to propose an optimal acquisition window for coronary MRA. Methods: Cine breath-hold x-ray angiograms with synchronous ECG were collected from 11 patients who underwent elective routine diagnostic coronarography. Twenty-three bifurcations of the left coronary artery were selected as markers to evaluate repositioning uncertainty and velocity during cardiac cycle. Each bifurcation was tracked by two observers, with the help of a user-assisted algorithm implemented in Matlab (The Mathworks, Natick, MA, USA) that compared the trajectories of the markers coming from consecutive heartbeats and computed the coronary repositioning uncertainty with steps of 50ms until 650ms after the R-wave. Repositioning uncertainty was defined as the diameter of the smallest circle encompassing the points to be compared at the same time after the R-wave. Student's t-tests with a false discovery rate (FDR, q=0.1) correction for multiple comparison were applied to see whether coronary repositioning and velocity vary statistically during cardiac cycle. Bland-Altman plots and linear regression were used to assess intra- and inter-observer agreement. Results: The analysis of left coronary artery beat-to-beat repositioning uncertainty shows a tendency to have better repositioning in mid systole (less than 0.84±0.58mm) and mid diastole (less than 0.89±0.6mm) than in the rest of the cardiac cycle (highest value at 50ms=1.35±0.64mm). According to Student's t-tests with FDR correction for multiple comparison (q=0.1), two intervals, in mid systole (150-200ms) and mid diastole (550-600ms), provide statistically better repositioning in comparison with the early systole and the early diastole. Coronary velocity analysis reveals that left coronary artery moves more slowly in end systole (14.35±11.35mm/s at 225ms) and mid diastole (11.78±11.62mm/s at 625ms) than in the rest of the cardiac cycle (highest value at 25ms: 55.96±22.34mm/s). This was confirmed by Student's t-tests with FDR correction for multiple comparison (q=0.1, FDR-corrected p-value=0.054): coronary velocity values at 225, 575 and 625ms are not much different between them but they are statistically inferior to all others. Bland-Altman plots and linear regression show that intra-observer agreement (y=0.97x+0.02 with R²=0.93 at 150ms) is better than inter-observer (y=0.8x+0.11 with R²=0.67 at 150ms). Discussion: The present study has demonstrated that there are two time intervals in the cardiac cycle, one in mid systole and one in mid diastole, where left coronary artery repositioning uncertainty reaches points of local minima. It has also been calculated that the velocity is the lowest in end systole and mid diastole. Since systole is less influenced by heart rate variability than diastole, it was finally proposed to test an acquisition window between 150 and 200ms after the R-wave.

The transmembrane serine protease (TMPRSS3) mutated in deafness DFNB8/10 activates the epithelial sodium channel (ENaC) in vitro.

TMPRSS3 encodes a transmembrane serine protease that contains both LDLRA and SRCR domains and is mutated in non-syndromic autosomal recessive deafness (DFNB8/10). To study its function, we cloned the mouse ortholog which maps to Mmu17, which is structurally similar to the human gene and encodes a polypeptide with 88% identity to the human protein. RT-PCR and RNA in situ hybridization on rat and mouse cochlea revealed that Tmprss3 is expressed in the spiral ganglion, the cells supporting the organ of Corti and the stria vascularis. RT-PCR on mouse tissues showed expression in the thymus, stomach, testis and E19 embryos. Transient expression of wild-type or tagged TMPRSS3 protein showed a primary localization in the endoplasmic reticulum. The epithelial amiloride-sensitive sodium channel (ENaC), which is expressed in many sodium-reabsorbing tissues including the inner ear and is regulated by membrane-bound channel activating serine proteases (CAPs), is a potential substrate of TMPRSS3. In the Xenopus oocyte expression system, proteolytic processing of TMPRSS3 was associated with increased ENaC mediated currents. In contrast, 6 TMPRSS3 mutants (D103G, R109W, C194F, W251C, P404L, C407R) causing deafness and a mutant in the catalytic triad of TMPRSS3 (S401A), failed to undergo proteolytic cleavage and activate ENaC. These data indicate that important signaling pathways in the inner ear are controlled by proteolytic cleavage and suggest: (i) the existence of an auto-catalytic processing by which TMPRSS3 would become active, and (ii) that ENaC could be a substrate of TMPRSS3 in the inner ear.